Check if number is decimal

You can get most of what you want from is_float, but if you really need to know whether it has a decimal in it, your function above isn't terribly far (albeit the wrong language):

function is_decimal( $val )
{
    return is_numeric( $val ) && floor( $val ) != $val;
}

if you want "10.00" to return true check Night Owl's answer

If you want to know if the decimals has a value you can use this answer.

Works with all kind of types (int, float, string)

if(fmod($val, 1) !== 0.00){
    // your code if its decimals has a value
} else {
    // your code if the decimals are .00, or is an integer
}

Examples:

(fmod(1.00,    1) !== 0.00)    // returns false
(fmod(2,       1) !== 0.00)    // returns false
(fmod(3.01,    1) !== 0.00)    // returns true
(fmod(4.33333, 1) !== 0.00)    // returns true
(fmod(5.00000, 1) !== 0.00)    // returns false
(fmod('6.50',  1) !== 0.00)    // returns true

Explanation:

fmod returns the floating point remainder (modulo) of the division of the arguments, (hence the (!== 0.00))

Modulus operator - why not use the modulus operator? E.g. ($val % 1 != 0)

From the PHP docs:

Operands of modulus are converted to integers (by stripping the decimal part) before processing.

Which will effectively destroys the op purpose, in other languages like javascript you can use the modulus operator

If all you need to know is whether a decimal point exists in a variable then this will get the job done...

function containsDecimal( $value ) {
    if ( strpos( $value, "." ) !== false ) {
        return true;
    }
    return false;
}

This isn't a very elegant solution but it works with strings and floats.

Make sure to use !== and not != in the strpos test or you will get incorrect results.

another way to solve this: preg_match('/^\d+\.\d+$/',$number); :)